Usb 2 Transfer Speed. Data transfer speed cable length usb 11. Advertised transfer rates are based on the fastest speed at which the drive can send data back and forth across the cable or bus from the drive buffer.

Advertised transfer rates are based on the fastest speed at which the drive can send data back and forth across the cable or bus from the drive buffer. This other document from cypress says near the end that they actually acheive 43 mbs. Update usb controller driver from device manager.
It is now obsolete but both of its speeds 15mbps 12mbps are being adopted into usb 20 and they are now called original usb officially.
The theoretical transfer speed of usb 30 is 48 gbits 600mbps vs. The serial ata drive and interface are faster than usb 20 so the usb 20 drive and interface are the bottleneck. According to this very informative document the theoretical maximum is 13 packets per microframe. Usb 20 devices are generally less expensive than usb 30 devices.